Inventive concepts relate to a method of manufacturing an integrated circuit device, and more particularly, to a method of manufacturing an integrated circuit device including patterns having a fine critical dimension (CD).
With the rapid development of down-scaling and large-scale integration of integrated circuit devices, new techniques for manufacturing integrated circuit devices with a reduced design rule are desired. For example, when only a photoresist pattern is used as a mask pattern during photolithography for realizing patterns having a fine CD, guaranteeing the dimensional accuracy of the patterns or devices to be formed may be difficult. When a mask pattern having multiple layers is used during photolithography, various etching processes for patterning the multiple layers are additionally used and lower structures may be damaged during the etching processes. As a result, manufacturing integrated circuit devices which have wanted dimensional accuracy and electrical characteristics may be difficult. Therefore, new processes for overcoming a resolution limit in photolithography and preventing, or reducing the likelihood of, lower patterns from being adversely affected during etching processes for patterning multiple layers are desired to be developed.